Muscular evaluation and exercising apparatus



2 Sheets-Sheet 1 H. W. M DONOUGH MUSCULAR EVALUATION AND EXERCISING APPARATUS INVENTOR. Hen/"y Wan/M 000 00gb IOI BY W -uQwkw, mm, c Mw T M J X ATTORNEYS Nov. 15, 1966 Filed June 26, 1963 Nov. 15, 1966 H. w MCDONOUGH 285,070

MUSCULAR EVALUATION AND EXERCISING APPARATUS 2 Sheets-Sheet 2 Filed June 26, 1963 T United States Patent 3,285,070 MUSCULAR EVALUATION AND EXERCISING APPARATUS Henry Wilmot McDonough, Dundee, 11]., assignor to Elgin Elmac Enterprises, Inc., a corporation of Illinois Filed June 26, 1963, Ser. No. 291,234 3 Claims. (Cl. 73-379) This invention relates to apparatus adapted for use in a program of physical development and/or rehabilitation. More particularly, the invention relates to apparatus for evaluating and increasing the strength of various muscles and muscle sets of the human body.

In various programs of muscular development and rehabilitation, it is desirable to determine the strength of various muscle sets of the body. For example, it may be desirable to periodically determine the effect of a particular physical training program on muscular development or, in the case of rehabilitation from a disabling injury or illness, it may be desirable to periodically determine the extent of recovery.

A frequently utilized method of evaluating the strength of a muscle or muscle set is to determine the distance which the associated portion of the body can be moved against a gradually increasing resistance as, for example, the resistance provided by an extended coil spring or a pivotally mounted weight. An evaluation thus obtained, however, does not generally provide an accurate indication of muscular strength due to the velocity and momentum of the moving parts of the body which introduce an additional energy factor into the system, and an evaluation obtained when the body is in a fixed position is far more accurate than one obtained while the body is moving. However, presently available apparatus are not capable of providing such an evaluation.

Also, apparatus which evaluate muscular strength incident to movement of the associated bodily parts do not give an indication of muscular strength over the entire range of motion of the bodily parts but, at best, are in dicative of the strength of the muscle set only at the point at which the strength of the muscle set is equal to the resistance provided by the springs or weights. It is Well known, however, that the strength of a muscle set varies over the range of motion of the associated bodily parts, and an isolated reading as can be obtained with available apparatus is therefore of little value.

It is the principal object of the present invention to provide an apparatus which can be used to evaluate the strength of various muscles and muscle sets of the body while the associated portions of the body are in a fixed position.

An additional object of the present invention is to provide an improved apparatus which is capable of evaluating the strength of certain of the muscle sets of the body in a series of fixed positions throughout the range of motion of the portions of the body to which these muscle sets are connected.

A further object of the invention is to provide an improved apparatus which is capable of providing an accurate indication of the strength of certain muscle sets of the body in various stationary positions of the portions of the body associated with these muscle sets, and which can alsoabe used in an application of the isometric prin ciple to provide exercise for the muscle sets in the various positions.

A still further object of the invention is to provide an improved strength evaluation and exercising apparatus with which an individual can obtain an indication of his muscular strength without assistance.

Another object of the invention is to provide an evaluation and exercising apparatus in which a single component is used for the testing of the muscles associated with several portions of the body.

Other objects and advantages of the invention will become apparent with reference to the following description and the accompanying drawings.

In the drawings:

FIGURE 1 is a perspective view of an apparatus showing various of the features of the invention;

FIGURE 2 is a slightly enlarged fragmentary partially broken-away perspective view of the apparatus of FIG- U FIGURE 3 is an enlarged fragmentary sectional view taken along line 33 of FIGURE 1;

FIGURE 4 is an enlarged fragmentary partially brokenaway plan view taken in the direction of the arrows 44 of FIGURE 1;

FIGURE 5 is a fragmentary partially broken-away end view on a reduced scale of the portion of the apparatus illustrated in FIGURE 3; and

FIGURES 6 through 9 are perspective views of the apparatus of FIGURE 1 showing certain of the manners in which the apparatus may be utilized.

The force which an individual can exert with any given muscle or muscle set depends to a great extent upon the relative positions of the portions of the body to which these muscles are connected. Thus, for example, the force which can be applied by the leg of an individual through an exertion of the hamstring muscles depends upon the angle formed at the knee by the bones of the upper and lower leg. Accordingly, in order for an evaluation of the strength of a muscle or muscle set to be significant and informative, it must provide an indication of the strength throughout the range of motion of the associated bodily parts.

The present invention is directed to an apparatus for evaluating the strength of various muscle sets over a range of motion of the associated body parts, particularly the legs, although the apparatus is also adapted for such an evaluation of the arm, abdominal, and back muscles as well. In this regard, the apparatus of the illustrated embodiment includes a body-supporting platform 11, a member 13 supported adjacent the body-supporting platform and adapted to remain essentially stationary while resisting a force exerted thereon by a user, the member 13 being adjustable to various positions relative to the platform, a sensing means 15 responsive to a force exerted on the member 13 by a user, and means 17 connected to the sensing means to indicate the amount of force exerted on the member by the user.

In the use of the apparatus, the member 13- is placed in a desired position adjacent that portion of the body of the user which is associated with the muscle set to be evaluated. For example, if it is desired to evaluate the strength of the leg muscles, the member may be placed in spaced relation to the edge of the platform and below the plane of the body-supporting surface of the platform. An individual supported on the platform 11 exerts his maximum force against the member, and the amount of the force is indicated by the indicating means 17. The member is then moved to a different position relativeto the platform and the individual again exerts his maximum force, which force is again indicated on the indicating means. This procedure may be repeated throughout the range of motion of the associated bodily part.

The apparatus of the present invention is also adapted to be used as a muscle strengthener through an application of the principle of isometric exercise. In accordance with this principle, muscles are developed when used to exert a force against an object which completely and effectively resists the force exerted .as, for example, exertion of the muscles against a stationary object. Ac-

of the apparatus of the present invention against the member 13 is also effective to strengthen the muscle set and can be utilized to develop the muscle set in various bodily positions, as when a position of relative weakness has been located.

More specifically, and with reference to the drawings, the body-supporting platform 11 comprises a rectangular rigid frame 19 supported in a generally horizontal and elevated position by four leg members 21 secured to the frame and extending downwardly therefrom in slightly diverging relation. The upper surface of the platform is defined by a flat plate 23 which overlies the frame 19 and is contiguous with the side and one of the end edges thereof, the plate being formed so as to provide a rolled wall 25 at one end of the platform, hereinafter referred to as the forward end. The rolled wall 25 provides a smooth surface at the forward end of the platform to accommodate the body of a user sitting at the forward edge with legs extending over the edge as in the position shown in FIGURE 6 of the drawings.

In order to assist the user in assuming a relatively fixed position on the platform 11 despite the application of a force by the user against an object adjacent the platform, retaining belts 27 are provided. Preferably, the ends of these belts are secured to slides (not shown) which travel in a guide track (not shown) mounted on the underside of the platform. The belts may thus be moved along the length of the platform to any desired location.

The member 13 is disposed adjacent an edge of the platform, the forward edge in the illustrated embodiment, and may be supported by various means such as, for example, a supporting assembly independent of the platform, or an elongated strut extending from the platform and straddled by the legs of the user when in certain evaluating positions.

In the illustrated embodimenghowever, the member 13 is supported adjacent the forward edge of the platform 11, and is rendered adjustable to various positions relative to the body-supporting surface of the platform, by a pair of horizontally spaced arm members 29, each of which extends outwardly from, and is rotatably carried adjacent, one of its ends by a mounting 31 located adjacent the forward portion of each of the side edges of the platform. The member 13 may be of various constructions but is preferably rigid and, in the illustrated embodiment, is in the form of a cylindrical bar. It should be understood, however, that a flexible member such as a strap would also be satisfactory if suitably connected to the sensing means 15. The member 13, hereinafter referred to as the rigid member, but as qualified above, is suitably carried on the arm members so as to be adjustable to various positions therealong and, in turn, supports the sensing means 15 which is connected to the indicating means 17 aflixed to one of the mountings 31 of the arm members 29.

More specifically, each of the arm members 29 is in the form of an elongated hollow tube of square cross section and includes four side walls, one of which is provided with a plurality of holes 33 spaced longitudinally therealong, the arms being preferably carried so that the side walls thereof which include the holes 33 face each other. The holes of each arm are adapted to receive a pin 35 of an assembly 37, soon to be described, by means of which the rigid member 13 is carried on the arms 29. The assembly 37 is slidable along the length of the arms 29 but is maintained in any one of a plurality of positions by the insertion of the pin 35 into one of the holes 33. The outer end of each arm, i.e., the end farthest from the platform 11, is capped as at 39 to prevent the assembly 37 from sliding past the ends of the arms.

As previously mentioned, each of the arm members extends -from a mounting 31 supported adjacent the forward end of the platform'll. Each mounting is of a generally hollow box-like construction (FIG. 2) and includes an elongated plate 41 forming an outer wall, a relatively narrow peripheral edge wall 43, and an inner wall 45 suitably secured to the frame 19 of the platform. The inner wall 45 of each mounting is cut away adjacent the upper forward edge thereof to expose the flat face of a circular disk 47 secured to and coaxial with a large spur gear 49 pivotally mounted on a stud (not shown) projecting inwardly from the outer plate 41 of the mounting. A pair of spaced apart flanges 51 project from the exposed faces of the disks, and each receives the inner end portion of one of the arm members 29.

Accordingly, it will be seen that the arm members pivot with the disk 47 and spur gear 49 about the axis defined by the stud on which the spur gear is mounted and are, therefore, adjustable to various angular positions relative to the body-supporting surface of the platform 11. Preferably, the axis defined by the stud is positioned slightly above the upper surface of the platform 11 and inwardly from the forward edge thereof so that the axis about which the arm members pivot substantially coincides with the axis about which the lower leg of the user pivot at the knee when the knees of the user are supported ad jacent the forward edge of the platform (FIGS. 6 and 7).

In order that the arm members may be moved in unison, each mounting 31 also contains a pinion gear 53 which is in meshing engagement with the spur gear 49 adjacent the lower portion of the periphery of the spur gear. The pinion gears of both mountings are keyed to a rod 55 which extends through the frame 19 of the platform beneath the upholstered plate 23 and is rotatably journalled in suitable holes in the mounting and frame. Accordingly, rotation of either of the pinion gears 53, as when one of the disks 47 is rotated, causes rotation of the opposite pinion gear and, hence, rotation of the opposite disk 47. Pivotal movement of either arm member 29, therefore, causes pivotal movement of the opposite arm member so that both members may be easily and simultaneously placed in any desired angular position.

In the actual evaluation of any muscle set, as well as in the exercise thereof, the rigid member 13 and, hence, arm members 29, are maintained in a stationary position and effectively resist any force exerted by the user which would tend to cause their movement. Locking of the arm members 29 in a desired angular position is accomplished 1n the illustrated embodiment by means of a rack 57 (FIG. 2) pivoted at one end within the mounting 31 and movable by means of a cam 59 so as to bring the teeth of the rack into engagement with the teeth of the pinion gear 53. Such engagement prevents the pinion gear from rotating and thus locks the arm members 29 in position. The cams 59 of each mounting are keyed to a rod 61 which extends through the frame 19 of the platform and is rotated by means of a handle or crank 63 located at each of its ends. Rotation of the rod, which can thus be accomplished from either side of the platform, is effective to rotate the cams and raise the rack into a locking position.

As previously mentioned, the arm members 29 have mounted thereon the assembly 37 which carries the rigid member 13, the assembly being slidably mounted on the arm members so as to permit adjustment therealong to various positions depending upon the portion of the body which is to be exercised.

More specifically, each of the arm members 29 carries an'elongated rectangular sleeve 65 (FIGS. 1 and 4) having an integral block 67 projecting upwardly therefrom and provided with a hole near its upper end to receive one end of the rigid member 13. The member 13 extends between the blocks of the sleeves of the adjacent arms and is held in place by set screws 69 extending through the blocks and into engagement with the member 13. The sensing means 15 is mounted on the rigid member centrally thereof in a manner which will be referred to in greater detail shortly.

Referring now to FIGURE 4, that side wall of each sleeve which is disposed adjacent the side wall of the arm member 29 provided with the series of holes 33 includes a hole 71 which is alignable with any One of the holes 33 and accommodates the pin 35 which, as previously mentioned, is adapted to occupy any of the aforementioned holes 33. The pin 35 is carried by one arm 73 of a rocker 75 comprising a channel-shaped member having arms 73 and 77 disposed at an obtuse angle to one another and pivotally mounted at the juncture of the arms on a dowel 79 supported by a pair of cars 81 projecting outwardly from the wall of the sleeve. The pin 35 projects downwardly from one of the arms adjacent the end thereof and is adapted to pass through the hole in the sleeve and into one of the series of holes in the adjacent side wall of the arm member 29 when the rocker is pivoted in a clockwise direction (FIG. 4) about the axis of the dowel. A compression spring 83 disposed intermediate the wall of the sleeve and the lower surface of the opposite arm 77 of the rocker maintains the rocker in a position in which the pin 35 is fully inserted into a hole in the arm member 29. The coil spring may be held in place by lugs (not shown) projecting from the sleeve and rocker.

When it is desired to move the assembly 37 along the arm members 29, the arm 77 of each rocker is depressed against the force of the compression spring 83 so as to withdraw the pin 35 from the holes 33 of the armmember. The sleeves 65 are then moved along their respective arm member until the desired position is reached, whereupon the pressure on each of the arms 77 is released and each of the pins 35 is allowed to become reinserted into a hole of its respective arm member. Accordingly, the rigid member 13 may be fixed in various positions on the arm members 29 to accommodate users'of various physical sizes, and to accommodate various evaluating and exercising positions of any individual user.

The sensing means 15 is adapted to be responsive to the force exerted on the rigid member 13 by the user, which may include responsiveness to forces on the arm members 29 as well as responsiveness to reaction forces on the platform 11. In the preferred embodiment, however, the sensing means -is mounted on the rigid member and is engaged directly by the body of the user. Hence, the forces are exerted on the rigid member through the sensing means. The sensing means is preferably responsive to both push and pull forces so that the user may exercise all of the muscles of the portion of the body engaging the sensing means.

More specifically, the sensing means comprises an outer housing 85 including an inverted U-shaped support of relatively heavy construction defining a top wall 87 and a pair of narrow end walls 89, and plates 91 and 93 defining the front and rear walls respectively of the housing. Each of the end walls 89 is provided with a hole adjacent its lower edge to receive the rigid member 13, and an elongated bolt 95 is threaded through a hole in the top wall 87 to engage the rigid member and limit rotation of the housing relative thereto. The bolt 95 is provided with a knob 97 at its upper end so that it might be released and the housing adjusted to various positions depending upon the portion of the body sought to be evaluated and/or exercised.

Disposed within the housing 85 is a yoke 99 in the form of an elongated block having a transverse hole 101 disposed in spaced relation to its lower end to receive the rigid member 13, this hole being of a slightly greater diameter than that of the rigid member in the direction of the longitudinal axis of the block to permit slight movement, e.g., A inch, of the block relative to the rigid member. The portion of the block which is positioned below the rigid member and hole has secured thereto a pad 103 against which the user can exert a pushing force. The pad is provided with a strap 105 which can be caused to encircle a portion of the body of the user, e.g., the

ankle, to permit the user to exert a pulling force on the pad as well. It will be appreciated with reference to FIGURE 3 that any force exerted on the pad 103 will tend to move the yoke 99 relative to the rigid member '13 in a direction parallel to the longitudinal axis of the yoke.

The upper portion of the yoke 99 is cut out to provide a rectangular opening 107 which is separated by a web 109 from the transverse hole 101 in which the rigid member 13 is disposed, and which is separated by a narrow top wall 111 from the upper end of the yoke. A transducer unit 113 is carried within the rectangular opening 107 and, as will become apparent shortly, converts the force exerted on the pad 103 into a fluid pressure which is transferred to the indicating means 17 to provide a visual reading indicating the amount of force applied to the pad 103.

The transducer unit 113 comprises a generally cylindrical body 115 which includes a lower section 117 and an upper section 119 threadedly interconnected and defining an internal cavity 121. The lower end of the lower section has a protruding abutment 123 which engages the upper surface of the web 109 of the yoke, and a hole 125 extends inwardly of the abutment to receive a pin 127 which also extends through an aligned hole in the web and into engagement with the rigid member 13. Accordingly, when the yoke is moved upwardly away from the rigid member, engagement between the abutment 123 and the web 109 causes the transducer unit to be moved upwardly with the yoke. However, when the yoke is moved downwardly in the direction of the rigid member, the pin 127 prevents the transducer unit from moving with the yoke. Consequently, when the yoke is moved downwardly, there is relative movement between the transducer unit and the yoke.

The interior of the lower section 117 of the transducer body 115 includes an annular shoulder 129 having an upstanding rib 131 on which a circular diaphragm 133 is supported, the rib 131 engaging the peripheral portion of the diaphragm. The upper section 119 of the transducer body includes a lower edge 135 which, when the upper and lower sections are assembled, is disposed immediately above the raised rib of the lower section and clamps the diaphragm to the upstanding rib. Accordingly, the diaphragm is suspended transversely across the cavity 121 of the transducer body.

The portion of the cavity 121 below the diaphragm 133 defines a reservoir 137 which is filled with an incompressible fluid such as a light oil. The reservoir is in communication with the indicating means 17, referred to in greater detail shortly, through a flexible conduit 139 connected to the transducer body 115 by means of a coupling 141 and extending through a suitable slot 143 in the outer housing 85 of the sensing means. Accordingly, it will be seen that pressures on the diaphragm 133 will be reflected in the pressure of the fluid in the reservoir, which pressure will be transmitted to the indicating means through the flexible conduit 139.

Force applied to the pad 103- is transmitted through the yoke 99 to the diaphragm 133 by means of a piston 145 which includes a flat circular disk 147 adapted to rest upon the upper surface of the diaphragm and a shank 149 projecting upwardly from the disk and outwardly of the transducer body 115 through a central bore provided in the upper section 119 of the body. The shank 149 of the piston is of such a length that it engages the lower surface of the top wall 111 of the yoke, thereby causing the piston to be moved downwardly when the yoke is moved downwardly. However, as has already been explained, the pin 127 prevents downward movement of the transducer body when the yoke moves downwardly. Accordingly, such downward movement of the yoke, caused by a pulling force on the pad 103, causes relative movement between the piston 145 and transducer body 115 and causes the fluid in the reservoir 137 to be placed under pressure.

The piston 145 is secured against upward movement by a pin 151, the lower portion of which is bottomed within a bore 153 of the shank 149 of the piston, and the upper portion of which is threaded into the top wall 87 of the housing 85 of the sensing means. The upper end of the pin 151 is provided with a slot to permit adjustment of the position thereof. Accordingly, it will be seen that upward movement of the yoke, as caused by a pushing force exerted on the .pad 103, carries the transducer body upwardly by virtue of the engagement between the abutment 123 of the body and the web 109 of the yoke. However, upward movement of the piston is prevented by the pin 151. Hence, there is again relative movement between the piston and transducer body such as places the fluid in the reservoir 137 under pressure.

It will be seen, therefore, that the sensing means 15 is responsive to forces exerted on the pad 103 although there is a relatively insignificant amount of movement or give of the pad. This feature provides an accurate response to the force applied and renders the apparatus suitable for the isometric form of exercise.

The function of the indicating means 17 is to provide an accurate indication of the force applied by the user to the pad 103 by virtue of the pressure created on the fluid carried within the fluid reservoir 137, the conduit 139, and the indicating means itself.v While the indicating means may be mounted at various locations to which a user supported on the platform 11 has visual access, the indicating means in the illustrated embodiment is carried in a housing secured to one of the mountings 31 adjacent the forward end of the body-supporting platform 11. Various forms of pressure-sensitive gauges may be employed, but a conventional Bourdon gauge in which the pressure created within the transducer unit is exerted on the interior of a metal tube (not shown), oval in cross section and bent to fit into a circular case, has been found to be preferable. The application of pressure tends to make the cross section of the tube round and thus to unroll or straighten the tube. This motion, connected by means of links, levers, a gear sector, and a pinion (not shown) rotates a hand about the calibrated dial, and the force in terms of pounds may be read.

The above-described apparatus has many applications, only a few of which will be explained herein. However, other applications will become readily apparent to those, for example, in the field of athletics, physical education, physical training, and physical therapy.

*One principal application of the apparatus is in the field of physical education and training. It has been found helpful, as an aid to the evaluation of the effectiveness of a particular program, to evaluate the muscular strength of the individual participants at the beginning of the program, and periodically throughout its duration. The rate of increase of muscular strength provides some indication of the successfulness of the program.

In another application, the strength of certain muscles, e.g., leg muscles, of athletes is evaluated when the athlete is in a good physical condition. If the athlete subsequently injures these muscles, their percentage of recovery can be determined by a comparison of current evaluation data with the basic data previously compiled.

Also, in the field of physical therapy wherein an individual is recovering from a disabling injury or disease, it is helpful to be able to determine the rate of recovery of, for example, the use of a limb. conventionally, this is accomplished by determining the amount of weight the individual can manipulate. However, the present apparatus provides more accurate and more graduated readings.

The present apparatus is also useful in connection with the principle of isometric exercising wherein an individual exerts a force against a resisting object, this activity being effective to develop the strength of the muscles exerted; With'the present apparatus, an individual can exert his maximum force against the rigid member 13, this being particularly helpful when it has been determined through evaluation that the muscles are weak between certain limits of the range of motion of the associated portions of the body.

Referring now to FIGURES 6 through 9 of the drawings, FIGURE 6 shows an individual supported on the platform 11 in a sitting position with his legs depending from the upper surface of the platfrom and with his lower foreleg engaging the pad of the sensing unit. In such a position, the individual can exercise and/or'evaluate the muscles of the upper and lower leg.

In the position shown in FIGURE'7, wherein the individual lies face down on the platform with the rearward portion of the lower leg engaging the pad, other of the leg and certain of the lower back muscles can be exercised and evaluated.

In the position shown in FIGURE 8, wherein the individual is lying on his back with the forward portion of the lower leg engaging the pad, certain of the leg, hip, and abdominal muscles can be exercised and evaluated.

In the position shown in FIGURE 9, wherein the individual is in a supine position and the pad engages the chest of the individual, the back and abdominal muscles can be exercised and evaluated.

It should be apparent that with the rigid member 13 disposed in various positions relative to the body-supporting platform 11, and with the user assuming various positions on the platform, the strength of many of the muscles can be evaluted. Also, using the same apparatus, the individual can exericse these same muscles by applying the isometric principle of exercising.

While various of the features of the invention have been shown and described, it should be apparent that various modifications may be made therein Without departing from the scope of the invention.

What is claimed is:

1. A strength-evaluation and exercising apparatus comprising an elongated elevated platform for supporting the body of a user, a pair of horizontally spaced arm members extending outwardly from one edge of the said platform and adapted to resist a force exerted thereon by a user, said arm members being adjustable to a plurality of angular positions relative to the body-supporting surface of said platform and being interconnected so that movement of one of the said arm members causes movement of the opposite arm member, means for locking said arm members in any one of the plurality of angular positions, a rigid cross arm slidably carried by said arm members and maintainable at various fixed positions therealong, sensing means mounted on said cross arm and engageable by a portion of the body of a user, said sensing means being responsive to a force exerted on the said aim members and cross arm by the user, and means connected to said sensing means for indicating the amount of force exerted on the said arm members and cross arm by user.

2. A strength-evaluation and exercising apparatus com prising an elongated elevated platform for supporting the body of a user, a pair of horizontally spaced arm members extending outwardly from one edge of the said platform and adapted to resist a force exerted thereon by a user, said arm members being pivotable about an axis disposed slightly, above the body-supportingsurface of the said platform so as to be adjustable to a plurality of angular positions relative to the body-supporting surface of said platform and being interconnected so that movement of one of the said arrn members causes movement of the opposite arm members, means for locking said arm members in any one of the plurality of angular positions, a cross arm slidably carried by said arm members and maintainable at various fixed positions therealong, sensing means mounted on said cross arm and engageable by a portion of the body of a user, said sensing means being responsive to a force exerted on the said arm members prising a platform for supporting the body of a user, at 5 least one arm member extending outwardly from one edge of said platform and adapted tolresist a force exerted thereon by a user, said arm member being adjustable to a plurality of angular positions relative to the bodysupporting surface of said platform, means for locking 10 said arm member in any one of the plurality of angular positions, a rigid cross arm slidably carried by said arm member and maintainable at various fixed positions therealong, sensing means mounted, on said cross arm and engageable by a portion of the body of a user, said sensing means being responsive to a force exerted thereon by the user, and means connected to said sensing means for indicating the amount of force exerted on said arm member and cross arm by the user.

References Cited by the Examiner UNITED STATES PATENTS 528,779 11/1894 Kellogg 73379 2,309,511 1/1943 Kellogg 73379 3,103,357 9/1963 Berne 73379 X OTHER REFERENCES D. R. Wilkie: The Relation Between Force and Velocity in Human Muscle, Journal of Physiology, vol. 110, 1949, page 270.

15 RICHARD C. QUEISSER, Primary Examiner.

DAVID SCHONBERG, Examiner. E. P. FORGRAVE, I. 1. SMITH, Assistant Examiners. 

3. A STRENGHT-EVALUATION AND EXERCISING APPARATUS COMPRISING A PLATFORM FOR SUPPORTING THE BODY OF A USER, AT LEAST ONE ARM MEMBER EXTENDING OUTWARDLY FROM ONE EDGE OF SAID PLATFROM AND ADAPTED TO RESIST A FORCE EXERTED THEREON BY A USER, SAID ARM MEMBER BEING ADJUSTABLE TO A PLURALITY OF ANGULAR POSITIONS RELATIVE TO THE BODYSUPPORTING SURFACE OF SAID PLATFORM, MEANS FOR LOCKING SAID ARM MEMBER IN ANY ONE OF THE PLURALITY OF ANGULAR POSITIONS, A RIGID CROSS ARM SLIDABLY CARRIED BY SAID ARM MEMBER AND MAINTAINABLE AT VARIOUS FIXED POSITIONS THEREALONG, SENSING MEANS MOUNTED ON SAID CROSS ARM AND ENGAGEABLE BY A PORTION OF THE BODY OF A USER, SAID SENSING MEANS BEING RESPONSIVE TO A FORCE EXERTED THEREON BY THE USER, AND MEANS CONNECTED TO SAID SENSING MEANS FOR INDICATING THE AMOUNT OF FORCE EXERTED ON SAID ARM MEMBER AND CROSS ARM BY THE USER. 